From U.S. Pat. Nos. 5,407,061 and 5,667,054, an overlapping slat conveyor with chain pitch adjustment using eccentric mechanism is known. These chain blocks are designed to cater for level slat conveyors having horizontal curves only. For multi-level slat conveyors which have to negotiate the level differences with vertical curves as well as horizontal curves to form a loop, a separate type of chain design is used as cited in U.S. Pat. No. 5,667,054. Also, this chain design is not truly multi-directional as the center of pivot axis of horizontal curve and vertical curve are not at the same point.
In a plant having both level as well as multi-level slat conveyors, usage of different type of chain blocks increases the inventory parts.
Also, the usage of slat conveyor having both horizontal as well as inclined portions is not possible with available chain design.